Fastener structure for housing means

ABSTRACT

A standard, including a plurality of circumferentially spaced downwardly opening cavities, is releasably connected to a support, which includes a plurality of mounting members each received within one cavity. A fastener is slidably inserted in each cavity, and is permanently retained therein by locking tabs that bite into the end walls of each cavity. Each fastener includes an opening having an enlarged portion adapted to be slidably positioned over a mounting member, and detent portions adjacent the enlarged portion which spread outwardly as the standard is rotated relative to the support. The fasteners include inclined retention portions on the opposite side of the opening from the enlarged portion which bite into the mounting members to positively prevent axial separation of the standard from the support.

United States Patent Corn et al.

[54] FASTENER STRUCTURE FOR HOUSING MEANS [72] inventors: Prentice R.Corn; Wallace A. Gebhardt, both of Logansport, Ind.

[73] Assignee: Switches, Incorporated [221 Filed: Dec. 14, 1970 [21]Appl. No.: 97,677

[52] US. Cl. ..200/l68 R, 74/531, 220/40 R [51] Int. Cl. ..H0lh 9/02[58] Ih'eld ofSearch ..24/2l1 K; 200/6l.54,61.55,

ZOO/61.56, 61.57,168 R, 168 B, 168 C, 166 CT, 168 G; 220/40 R; 74/531Wittenberg ..220/40 R Adams et al. ..200/ 168 G Primary Examiner-H. 0.Jones Att0rneyDressler, Goldsmith, Gordon & Ladd ABSTRACT A standard,including a plurality of circumferentially spaced downwardly openingcavities, is releasably connected to a support, which includes aplurality of mounting members each received within one cavity. Afastener is slidably inserted in each cavity, and is permanentlyretained therein by locking tabs that bite into the end walls of eachcavity. Each fastener includes an opening having an enlarged portionadapted to be slidably positioned over a mounting member, and detentportions adjacent the enlarged portion which spread outwardly as thestandard is rotated relative to the support. The fasteners includeinclined retention portions on the opposite side of the opening from theenlarged portion which bite into the mounting members to positivelyprevent axial separation of the stan dard from the support.

25 Claims, 8 Drawing Figures FASTENER STRUCTURE FOR HOUSING MEANSBACKGROUND OF THE INVENTION In many diverse environments it is desirableto provide a connection between two members that will positively holdthe members against separation by the movement of one member relative tothe other member in a given direction, but which will readily allow themembers to be separated when one member is moved relative to the othermember in another direction. For example, it is often desirable toconnect two members together in a manner so as to positively preventaxial separation of the members, while at the same time providing acapability for separating the members from one another, as by rotatingone element relative to the other element.

Heretofore, structural arrangements for a connection of the typedescribed above have not always been satisfactory, in that sucharrangements have not provided a sufficiently positive separationprevention means, or have been so complex and costly as to make thearrangement economically unfeasible, even though the separationprevention means was positive. Prior art arrangements have also beencharacterized by being difficult to assemble and disassemble, and veryoften components of the structural arrangement were irreparably damagedduring either the assembly or disassembly steps.

SUMMARY OF THE INVENTION The present invention obviates the problemsnoted above by providing a unique fastener member which cooperates witha novel standard to provide a connection means that may be easily andquickly assembled without damaging the components, which positively holdthe standard against axial separation relative to a support onceassembled, and which allows the standard to be quickly and easilydisassembled from the support, when desired, without damage to any ofthe structural components.

The standard of the present invention has particular utility as areinforcing member in a momentary switch of the type that is mounted onthe steering column of a vehicle. Such a switch is disclosed in detailand claimed in the commonly assigned Wolf et al. application, Ser. No.94,240 entitled IM- PROVED MOMENTARY CONTACT SWITCH filed Dec. 1, 1970,and the disclosure of such application is hereby expressly incorporatedby reference in its entirety in the present application.

The standard of the present invention includes a plurality ofcircumferentially spaced downwardly opening cavities that areinterconnected by arcuate upright members. Each cavity is defined byarcuate inner and outer, or side, walls that are parallel with oneanother and that are connected at their outer ends by planar end wallswhich converge toward one another from the outer side wall to the innerside wall. Intermediate walls are provided in closely spaced, parallelrelationship with each end wall to divide each cavity into an enlargedcentral compartment flanked by narrow upright slideways. A fastener isslidably inserted in each cavity, and is positively retained therein.

Each fastener includes a generally planar base section having a centralopening therein that is arcuate and positioned in alignment with thecentral compartment ofits respective cavity. Each fastener includes apair of legs that extend perpendicularly outwardly from opposite ends ofthe base section, with each leg being slidably received in one of theaforementioned upright slideways. Inclined locking tabs are struckoutwardly from each leg of the fastener, and the tabs do not interferewith the slidable insertion of the fastener into the cavity; however,the free ends ofthe tabs are provided with a pronged lockingconfiguration that positively prevents the fasteners from being removedfrom the cavities by virtue of the biting engagement of the prongs withthe end walls of the cavity.

The base portion of each fastener is generally flat and coplanar, andportions thereof are positioned in face abutting engagement withportions of the bottom surface of the sidewalls of the standardcavities. The sidewalls of the cavities include clearance notches thatallow arcuate detent portions of the fastener to flex outwardly when thestandard is assembled to a support. The support includes a plurality ofupright mounting members that impale the openings in the fasteners, andthe detent portions of the fasteners restrict the width of the openingto a dimension less than the diameter of the fastener member. Theportion of the opening of each fastener at one side of the detent has awidth that is slightly in excess of the diameter of the fasteningmembers, so that the standard may be readily positioned over the supportprior to movement of the standard relative to the support, and theportion of the opening of the fasteners on the opposite side of thedetents include inclined flanges that bite into opposite sides of themounting members to positively prevent the standard from being axiallyseparated from the support.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view,partly in section, illustrating a preferred form of the fasteningstructure of the present invention;

FIG. 2 is a bottom plan view, partly in section, taken generally alongline 2-2 of FIG. 1;

FIG. 3 is an enlarged sectional view taken generally along line 3-3 ofFIG. 1;

FIG. 4 is a sectional view taken generally along line 44 of FIG. 3;

FIGS. 5, 6, and 7 are sectional views taken generally along lines 55,6-6, and 77, respectively, of FIG. 4; and

FIG. 8 is a view similar to FIG. 3, and illustrates a further embodimentof the invention.

DETAILED DESCRIPTION While this invention is susceptible of embodimentin many different forms, there is shown in the drawings and will hereinbe described in detail a preferred embodiment of the invention, and amodification thereof, with the understanding that the present disclosureis to be considered as an exemplification of the principles of theinvention and is not intended to limit the invention to the embodimentillustrated. The scope of the invention will be pointed out in theappended claims.

Referring now to the drawings in detail, the connection assembly of thepresent invention is illustrated in its entirety at 10 in FIG. 1 andincludes a standard 12 that is adapted to be connected to a support 14,such as the steering wheel of a motor vehicle. Standard 12 includes aplurality of circumferentially spaced, downwardly opening cavities 16,each of which has a fastener member 18 mounted therein. Upright mountingmembers 20 are fixed to support 14 at circumferentially spaced locationscorresponding to the spacing of cavities 16, and each member 20 impalesa cavity 16 to releasably mount the standard 12 on the support 14, aswill hereinafter appear.

Standard 12 is formed of an electrically insulating material, such as asuitable plastic, and includes a generally frustoconical outer wall 22.Cavities 16 are spaced radially inwardly of outer wall 22, and as can bebest seen in FIG. 3, each cavity 16 is circumscribed by an arcuate innerside wall 24, an arcuate outer side wall 26 parallel with wall 24, andplanar end walls 28 that converge toward one another from outer wall 26to inner wall 24. Cavity side walls 24 and 26 include clearance notches32 and 34, respectively, at the lower end thereof that allow portions ofthe fasteners 18 to flex outwardly during assembly, as will hereinafterappear. Each cavity 16 further includes intermediate wall means 36,defined by spaced wall sections 38, that are parallel with end walls 28in close proximity thereto. Wall sections 38 cooperate with end walls 28to provide narrow vertical slideways 40 (FIG. 4) at each end of cavities16, and to provide an enlarged arcuate compartment 42 centrally ofeachcavity.

Each fastener 18 includes a base portion 44 having a central opening 46(FIG. 4) therein, and base portion 44 is defined by flat, generallyarcuately shaped inner and outer portions 48 and 50, respectively, thatare connected by end portions 52 that converge from outer portion 50toward inner portion 48. As is evident from FIG. 6, the lower portion ofeasing side walls 24 and 26, on opposite sides of notches 32 and 34,respectively, are provided with coplanar bottom portions 240 and 26athat provide bearing surfaces that are positioned in face abuttingengagement with fastener base portions 48 and 50, respectively.

Fasteners 18 are provided with legs 54 at opposite ends thereof that aredisposed perpendicularly with respect to base 44, and which are slidablyreceived in slideways 40. Each leg 54 is provided with an outwardlystruck inclined tab 56 that is provided with a locking configuration atthe free end thereof, which includes a recessed c'entral portion 58(FIG. 7) that provides sharpened prongs 60 at opposite sides of each tab56. Fasteners 18 are preferably formed ofa metallic material that issubstantially harder than the material from which casing 12 is formed,so that while the fasteners 18 may be freely slidably inserted withinthe cavities 16, the prongs 60 will positively bite into the end walls28 to positively and effectively prevent removal of the fasteners 18from the standard 12 once they have been inserted in the cavity.

Fasteners 18 further include detents 62 and 64 that extend generallyperpendicularly with respect to base portion 44. Detents 62 and 64extend upwardly into cavities 16 from base portions 48 and 50,respectively, with detent 62 being aligned with notch 32 and detent 64being aligned with notch 34, as can be readily seen in FIG. 5. As isevident from FIG. 3, detents 62 and 64 are arcuate in cross section toprovide a camming surface that is engageable with mounting members 20,as will herein after appear. The facing portions of detents 62 and 64serve to restrict the width of the opening 46 in the base portion 44 ofthe fasteners 18, and the width of the restricted passage portion 66 isless than the diameter of mounting members 20.

The openings 46 in fasteners 18 include holding means 68 at one side ofdetents 62 and 64, with the holding means being defined by inclinedflanges 70 that extend upwardly at an angle with respect to baseportions 48 and 50, as can be best seen in FIG. 6. The free ends offlanges 70 are spaced apart by a distance that is less than the diameterof mounting members 20, so that as the standard 12 is rotated relativeto the support 14 to move the flanges 70 into engagement with themounting members 20, a positive axial retention force is provided byvirtue of the capability of the flanges 70 to bite into the relativelysofter mounting members 20. Webs 72 extend radially outwardly fromcavity walls 26 to the outer wall 22 of standard 12 outwardly of flanges70 to reinforce the holding means after the reinforcing member has beenassembled to the support.

While the mounting structure of the present invention is not limited toany particular environment, as is mentioned above, the structure of thepresent invention has particular utility in connection with theconnection of a momentary horn switch to the steering wheel of a motorvehicle. As is described in detail in the concurrently filed applicationmentioned above, the top surface 74 (FIG. 2) of the standard 12 isirregularly shaped and supports switch contacts (not shown) in anannular upwardly facing recess adjacent the upper end thereof. Theswitch contacts are held in spaced relationship with respect to oneanother by annular insulation members (not shown), and connectionportions of the contacts extend downwardly through openings 76 in thetop wall 74 of the standard 12. A diametrically extending bar 78 extendsbelow top wall 74 to support the terminal wires (not shown) that aresecured to the connection portions of the switch contacts that extendthrough openings 76, as is also explained in the above mentionedconcurrently filed application. A generally frustoconically shapedresilient housing 80 surrounds the standard 12, and the flexible upperportion of casing 80 is manually depressable to move the switch contactsinto engagement with one another to complete an electric circuit to ahorn switch, or the like, as is explained in detail in the abovementioned concurrently filed application. The casing 80 includes aflanged configuration 82 at the lower end thereof that mates with aflanged configuration at the upper end support 14, in an exemplaryembodiment of the invention.

While the connection means of the present invention has been heretoforedescribed as having particular utility in connection with a momentarycontact switching device, it should be understood that the presentinvention is not limited to any particular environment, and in fact, hasgeneral utility in many environments where it is desired to detachablyconnect one member to another member.

In operation, the fastener members 18 are initially slidably insertedinto each of the cavities 16. The inclination of the tabs 56 on legs 54of the fastener members allow the legs 54 of the fasteners to be freelyslidably inserted within the slideways 40. The locking configurationprovided by prongs 60 provides a positive retention means that preventsthe fasteners 18 from being axially disassociated from the support 14.

The mounting members 20 and the cavities 16 have a predetermined angularorientation relative to one another so that the standard 12 can beassembled on the support 14 in only one position. In this respect, withreference to FIG. 2, the left-hand cavity 16 may be spaced from theupper cavity 16 by an angular amount that is essentially equal to theangular spacing between the upper cavity 16 and the right-hand cavity16. while the left-hand and right-hand cavities 16 are spaced from oneanother by a larger angle. The mounting members 20 have a correspondingangular orientation, and in this manner, proper alignment of thestandard 12 relative to the support 14 is insured.

Since the base portions 48 and 50 are positively seated against thebacking surfaces 24a and 26a ofthe cavity walls 24 and 26, if it isattempted to assemble an improperly aligned standard 12 to the support14. the fasteners 18 will not be damaged since surfaces 240 and 26::will effectively resist deformation of the fasteners. Since the openings46 in the fasteners include an end portion that is slightly larger indiameter than the mounting members 20, once the standard 12 is properlyangularly oriented relative to the support 14, the standard 12 may bemoved axially downwardly relative to the support, so that the fasteners20 impale the ends of openings 46 opposite from the holding means 68.The upper ends of mounting members 20 are preferably tapered tofacilitate the positioning of the standard 12 relative to the support14.

Once the standard 12 has been telescoped over the mounting members 20,with the flanged configuration 82 in position over the upper end ofsupport 14, the standard 12 is rotated in a clockwise direction and themounting members 20 cause the arcuate detent portions 62 and 64 to flexoutwardly as the mounting members move therepast. Openings 32 and 34 incasing walls 24 and 26, respectively, allow the detent portions 62 and64 to flex outwardly during movement of the mounting members 20 relativethereto. Continued clockwise movement of the standard 12 relative to thesupport 14 causes the detents 62 and 64 to clear the mounting members20, whereupon the inclined flange portions bite into diametricallyopposed portions of the mounting members 20 to positively prevent thestandard 12 from being axially separated from the support 14.

The detents 62 and 64 restrict the openings 46 in the fasteners to anextent that the standard 12 cannot be moved counterclockwise relative tothe support 14 by vibration or other incidental forces applied theretoduring use. However, if it is desired to remove the standard 12 from thesupport 14, the detenting forces can be overcome by moving the standard12 in a counterclockwise direction so that the detents 62 and 64 willclear the mounting members 20 and allow the mounting members to moveinto the enlarged portions of openings 46 so that the standard 12 can beaxially displaced from the support 14.

While the present invention has illustrated three downwardly openingcavities in a standard, and a fastener in each opening, it should beunderstood that the invention is not limited to any specific numbers ofcavities or fasteners, and

that more or less than three can be utilized without departing from thespirit and scope ofthe present invention.

Furthermore, while the cavities and fasteners have been illustrated ashaving an arcuate configuration, the present invention is not limited toany specific shaped structures or openings, and linear slots or openingsof other configurations may be utilized, if desired.

In FIG. 8, a further embodiment of the invention is illustrated that issimilar to the previously described embodiment, so that similarreference numerals have been used to designate corresponding elements,with the reference numerals in FIG. 8 having been increased by the sum100. The fastener 118 of FIG. 8 differs essentially from the previouslydescribed embodiment in that the base portion of the fastener isgenerally rectangular and defined by spaced parallel side walls 148 and150 and spaced parallel end walls 152 disposed perpendicularly withrespect to side walls 148 and 150. The fastener 118 includes verticallegs 154 having outwardly struck tabs 156 thereon, with the legs 154being slidably positionable within spaced parallel slideways in thecavity 116 ofstandard 112.

As with the previously described embodiment, fastener 118 includesarcuate detent portions 162 and 164 extending outwardly from base sides148 and 150, respectively, with flanges 170 being provided on baseportions 148 and 150 at one side of detents 162 and 164. It will bereadily understood that in use, the casing 112 is positioned over amounting member, not shown, and the casing 112 is moved rectilinearlyrelative to the mounting member which spreads the detents 162 and 164outwardly and enables the holding flanges 170 to bite into diametricallyopposed portions of the mounting member to positively secure thestandard 112 to the mounting member.

What is claimed is:

I. A fastener comprising: a substantially flat base having an elongateopening therein; first and second legs extending generally perpendicularwith respect to said base at opposite ends thereof, each leg having anoutwardly extending locking portion adapted to engage a wall of a cavityto prevent removal of the fastener from the cavity; a detent at one sideof said opening between the ends thereof, said detent extendinggenerally perpendicularly with respect to said base and partiallyrestricting said opening; and holding means on said base at one side ofsaid detent and extending into said opening to provide a means forpositively engaging a mounting member.

2. A fastener as set forth in claim 1 in which said base. legs anddetent and holding means are all portions of a unitary metallic member.

3. A fastener as set forth in claim 1 in which said legs and detentextend in the same direction away from said base.

4. A fastener as set forth in claim 1 in which said locking portions areeach defined by a tab struck from its respective leg, each tab having alocking configuration at the free end thereof.

5. A fastener as set forth in claim 4 in which each tab is struckoutwardly from its respective leg with its free end facing toward saidbase.

6. A fastener as set forth in claim 5 in which the free end of each tabhas a recessed central portion providing spaced prongs which providesaid locking configuration.

7. A fastener as set forth in claim 1 in which a pair of detents and apair of holding means are provided at opposite sides of said opening.

8. A fastener as set forth in claim 7 in which said detents are arcuatein cross section.

9. A fastener as set forth in claim 7 in which said holding means aredefined by wall sections inclined away from said base.

10. A fastener as set forth in claim 1 in which said base includesspaced inner and outer arcuate walls connected at their outer ends byend walls that converge from said outer wall toward said inner wall,said walls being disposed in a common plane and bordering said openingwhich has an arcuate configuration.

11. A fastener as set forth in claim 1 in which said base and saidopening are generally rectangular, said base being defined by spacedpaRallel side walls and spaced parallel end walls perpendicular to saidside walls.

12. In combination: a support including a mounting member; a standardmounted on said support and connected to said mounting member, saidstandard including a downwardly opening cavity defined by spaced endwalls and spaced side walls, the bottom of said side walls includinggenerally coplanar portions forming a bearing surface; a fastenerpositioned in said cavity and including a substantially flat base havingan opening therein impaled by said mounting member, portions of saidbase being positioned in surface abutting engagement with said bearingsurface, first and second legs extending generally perpendicularly withrespect to said base at opposite ends thereof, each leg extendingupwardly into said cavity adjacent an end wall thereof and each leghaving an outwardly extending locking portion engaging the adjacent endwall to prevent removal of the fastener member from the cavity, a detentat one side of said opening between the ends thereof, said detentextending generally perpendicularly with respect to said base andrestricting said opening to a dimension less than the transversedimension of the mounting member, and holding means on said base at oneside of said detent and extending into said opening to provide a meansfor positively engaging said mounting member.

13. The combination of claim 12 in which said standard includesintermediate walls spaced from and parallel with said end walls anddividing the cavity into an enlarged central compartment receiving saidmounting member and narrow upright slideways flanking said centralcompartment and receiving the legs of said fastener therein.

14. The combination of claim 12 in which said standard includes aplurality of generally identical cavities at circumferentially spacedlocations, each cavity having one of said fasteners therein, saidcavities being joined by upright arcuate members, and wherein a mountingmember impales the opening of each of said fasteners.

15. The combination of claim 14 in which said standard includes acircumferentially continuous member outwardly of said upright membersand cavities, and wherein radial ribs extend between one side wall ofeach cavity and said circumferentially continuous member.

16. The combination of claim 15 wherein each of said ribs is radiallyaligned with the holding means of one of said fasteners.

17. The combination of claim 14 in which each of said mounting membershas a tapered upper end to facilitate the assembly ofsaid standard tosaid mounting members.

18. The combination of claim 12 in which said fastener includes a pairof detents at opposite sides of said opening, and wherein the side wallsof the cavity of said standard include clearance notches in alignmentwith said detents to allow said detents to flex outwardly when saidstandard is moved relative to said mounting member.

19. A standard adapted to be mounted on a support comprising: an uprightmember; means associated with said upright member forming a downwardlyopen cavity defined by spaced end walls and spaced side walls, thebottom of said side walls including generally coplanar portions forminga bearing surface; and intermediate wall means spaced from and parallelwith each end wall and dividing the cavity into an enlarged centralcompartment flanked by narrow upright slideways.

20. A standard as set forth in claim 19 in which said end walls areplanar and disposed at an angle with respect to one another.

21. A standard as set forth in claim 19 in which said side walls arearcuate and parallel with one another.

22. A standard as set forth in claim 19 in which said side walls arearcuate and parallel with one another, one of said side walls having agreater arcuate length than the other of said side walls; and whereinsaid end walls are planar and converge from said one side wall to saidother side wall.

of said cavities is offset angularly relative to the other cavities.

25. A standard as set forth in claim 19 wherein said upright member andwalls are all portions ofa unitary member formed of electricallyinsulating material.

1. A fastener comprising: a substantially flat base having an elongateopening therein; first and second legs Extending generally perpendicularwith respect to said base at opposite ends thereof, each leg having anoutwardly extending locking portion adapted to engage a wall of a cavityto prevent removal of the fastener from the cavity; a detent at one sideof said opening between the ends thereof, said detent extendinggenerally perpendicularly with respect to said base and partiallyrestricting said opening; and holding means on said base at one side ofsaid detent and extending into said opening to provide a means forpositively engaging a mounting member.
 2. A fastener as set forth inclaim 1 in which said base, legs and detent and holding means are allportions of a unitary metallic member.
 3. A fastener as set forth inclaim 1 in which said legs and detent extend in the same direction awayfrom said base.
 4. A fastener as set forth in claim 1 in which saidlocking portions are each defined by a tab struck from its respectiveleg, each tab having a locking configuration at the free end thereof. 5.A fastener as set forth in claim 4 in which each tab is struck outwardlyfrom its respective leg with its free end facing toward said base.
 6. Afastener as set forth in claim 5 in which the free end of each tab has arecessed central portion providing spaced prongs which provide saidlocking configuration.
 7. A fastener as set forth in claim 1 in which apair of detents and a pair of holding means are provided at oppositesides of said opening.
 8. A fastener as set forth in claim 7 in whichsaid detents are arcuate in cross section.
 9. A fastener as set forth inclaim 7 in which said holding means are defined by wall sectionsinclined away from said base.
 10. A fastener as set forth in claim 1 inwhich said base includes spaced inner and outer arcuate walls connectedat their outer ends by end walls that converge from said outer walltoward said inner wall, said walls being disposed in a common plane andbordering said opening which has an arcuate configuration.
 11. Afastener as set forth in claim 1 in which said base and said opening aregenerally rectangular, said base being defined by spaced paRallel sidewalls and spaced parallel end walls perpendicular to said side walls.12. In combination: a support including a mounting member; a standardmounted on said support and connected to said mounting member, saidstandard including a downwardly opening cavity defined by spaced endwalls and spaced side walls, the bottom of said side walls includinggenerally coplanar portions forming a bearing surface; a fastenerpositioned in said cavity and including a substantially flat base havingan opening therein impaled by said mounting member, portions of saidbase being positioned in surface abutting engagement with said bearingsurface, first and second legs extending generally perpendicularly withrespect to said base at opposite ends thereof, each leg extendingupwardly into said cavity adjacent an end wall thereof and each leghaving an outwardly extending locking portion engaging the adjacent endwall to prevent removal of the fastener member from the cavity, a detentat one side of said opening between the ends thereof, said detentextending generally perpendicularly with respect to said base andrestricting said opening to a dimension less than the transversedimension of the mounting member, and holding means on said base at oneside of said detent and extending into said opening to provide a meansfor positively engaging said mounting member.
 13. The combination ofclaim 12 in which said standard includes intermediate walls spaced fromand parallel with said end walls and dividing the cavity into anenlarged central compartment receiving said mounting member and narrowupright slideways flanking said central compartment and receiving thelegs of said fastener therein.
 14. The combination of claim 12 in whichsaid standard includes a plurality of generally identical cavities atcircumferentially spaced locations, each cavity having one of saidfastEners therein, said cavities being joined by upright arcuatemembers, and wherein a mounting member impales the opening of each ofsaid fasteners.
 15. The combination of claim 14 in which said standardincludes a circumferentially continuous member outwardly of said uprightmembers and cavities, and wherein radial ribs extend between one sidewall of each cavity and said circumferentially continuous member. 16.The combination of claim 15 wherein each of said ribs is radiallyaligned with the holding means of one of said fasteners.
 17. Thecombination of claim 14 in which each of said mounting members has atapered upper end to facilitate the assembly of said standard to saidmounting members.
 18. The combination of claim 12 in which said fastenerincludes a pair of detents at opposite sides of said opening, andwherein the side walls of the cavity of said standard include clearancenotches in alignment with said detents to allow said detents to flexoutwardly when said standard is moved relative to said mounting member.19. A standard adapted to be mounted on a support comprising: an uprightmember; means associated with said upright member forming a downwardlyopen cavity defined by spaced end walls and spaced side walls, thebottom of said side walls including generally coplanar portions forminga bearing surface; and intermediate wall means spaced from and parallelwith each end wall and dividing the cavity into an enlarged centralcompartment flanked by narrow upright slideways.
 20. A standard as setforth in claim 19 in which said end walls are planar and disposed at anangle with respect to one another.
 21. A standard as set forth in claim19 in which said side walls are arcuate and parallel with one another.22. A standard as set forth in claim 19 in which said side walls arearcuate and parallel with one another, one of said side walls having agreater arcuate length than the other of said side walls; and whereinsaid end walls are planar and converge from said one side wall to saidother side wall.
 23. A standard as set forth in claim 22 in which saidupright member is annular, and wherein a plurality of cavities areprovided at circumferentially spaced positions around said annularmember.
 24. A standard as set forth in claim 23 in which at least one ofsaid cavities is offset angularly relative to the other cavities.
 25. Astandard as set forth in claim 19 wherein said upright member and wallsare all portions of a unitary member formed of electrically insulatingmaterial.